Patent US5103106A successfully refreshed from Google Patents.
US5103106A
Expired / Lapsed
US
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Reflective optical instrument for measuring surface reflectance
Assignee: Individual
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Filing: 1991-03-20
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Granted: 1992-04-07
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Expires: 2011-03-20
Abstract
Abstract An optical instrument for measuring characteristics of a specimen comprising a light source to project a beam onto the surface of a specimen at a selected oblique angle of incidence β. The instrument also contains a photosensor to receive the beam reflected from the specimen at the same angle β. A conductor connected to the photosensor is provided for carrying current to signal conditioning hardware used to compare the current from two or more photosensors or, if present, from different segments of the same photosensor to provide information concerning the specimen. Photosensor means is also positioned facing the specimen on an optical axis located normal to the surface of the specimen and intermediate the incident and reflected beams from the light source to receive a beam reflected from the specimen normal to its surface, i.e., along the optical axis. Signals from the photosensors are fed to the signal conditioning hardware to measure the optical power and to compare signals for measuring characteristics of the surface, e.g., its reflectivity or reflectance and to locate its position and/or orientation with respect to the instrument.
Inventors
- 👤 Moshe Golberstein
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 14:11
CPC Classifications
G; G01; G01B; G01B11/00; G01B11/30; G01B11/303; G01B11/02; G01B11/026; G01N; G01N21/00; G01N21/17; G01N21/55; G01J; G01J1/00; G01J1/10; G01J1/16; G01J1/1626; G01J2001/1652
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
201 words
An optical instrument for measuring the characteristics of a specimen having a surface comprising, a light source to provide a beam of light directed at an oblique angle β with respect to the normal of the surface, said beam being reflected from the surface at the same angle β with respect to the normal of the surface, said instrument having an optical axis normal to the specimen, a first photosensor means optically aligned with the reflected beam for receiving the reflected beam when the specimen is at a selected standoff distance from the instrument, said photosensor including means to detect movement of the reflected beam thereon responsive to changes in the distance of the instrument from the standoff distance and to changes in the orientation of the surface with respect to the instrument which alters the point at which the reflected beam strikes the photosensor, said photosensor thereby providing signals responsive to changes in the orientation and distance between the specimen and the instrument, means providing a second beam of light directed away from the specimen along said optical axis, and a second photosensor means optically positioned to receive the second beam of light for measuring a characteristic of the specimen.
Claim 2
Dependent Claim
201 words
An optical instrument for measuring the characteristics of a specimen having a surface comprising, a light source to provide a beam of light directed at an oblique angle β with respect to the normal of the surface, said beam being reflected from the surface at the same angle β with respect to the normal of the surface, said instrument having an optical axis normal to the specimen, a first photosensor means optically aligned with the reflected beam for receiving the reflected beam when the specimen is at a selected standoff distance from the instrument, said photosensor including means to detect movement of the reflected beam thereon responsive to changes in the distance of the instrument from the standoff distance and to changes in the orientation of the surface with respect to the instrument which alters the point at which the reflected beam strikes the photosensor, said photosensor thereby providing signals responsive to changes in the orientation and distance between the specimen and the instrument, means providing a second beam of light directed away from the specimen along said optical axis, and a second photosensor means optically positioned to receive the second beam of light for measuring a characteristic of the specimen.
Claim 3
Dependent Claim
89 words
The optical instrument of claim 1 wherein beam redirecting means is provided for redirecting the reflected beam onto the specimen along said optical axis, means is provided for directing an additional beam of light along the optical axis onto the surface of the specimen, and a beam blocking means is provided for intercepting the redirected beam to then prevent oblique illumination of the surface of the specimen for isolating the measurement of at least one of said photosensor means to illumination reflected from the specimen at a single angle.
Claim 4
Dependent Claim
72 words
The optical instrument of claim 2 wherein a first axial reflective means is provided for deflecting the reflected beam onto the specimen along said optical axis, a second reflective means is positioned on the optical axis for deflecting a beam from a second source of light along the optical axis onto the surface of the specimen and said beam blocking means is a shutter located between the two axially positioned reflective means.
Claim 5
Dependent Claim
46 words
The optical instrument of claim 2 wherein said photosensor means are connected to signal conditioning circuitry means, said signal conditioning circuitry includes means for activating and deactivating the beam blocking means to thereby prevent oblique illumination of the surface of the specimen at a selected time.
Claim 6
Dependent Claim
47 words
The optical instrument of claim 1 including lenses positioned to reduce the size of light spots projected by said beams onto the surface of the specimen to thereby improve measurement of longitudinal and angular deviation of the surface with respect to the optical axis of the instrument.
Claim 7
Dependent Claim
66 words
The optical instrument of claim 1 having a selectively operable means for measuring angular displacement of the specimen with respect to the optical axis of the instrument and for measuring longitudinal displacement of the surface of the specimen along the optical axis whereby angular and longitudinal displacement of the specimen from said standoff position can be measured separately, thereby improving the accuracy of said displacement measurements.
Claim 8
Dependent Claim
85 words
The optical instrument of claim 1 including a double-sided, back-to-back photosensor optically aligned with said beam of light positioned normal to the surface of the specimen on the optical axis of the instrument, said double-sided photosensor having an apertured and segmented photosensor on a side thereof facing away from the specimen and a second non-apertured photosensor on a side thereof facing the specimen, said non-apertured photosensor being transparent to light projected from the light source and being adapted to sense radiation emanating from the specimen.
Claim 9
Dependent Claim
60 words
The optical instrument of claim 7 wherein signal conditioning circuitry is connected to the double-sided, back-to-back photosensor for independent measurement of a) the angular displacement of the surface and b) the longitudinal displacement of the surface from a known standoff position, and one of said photosensor means is directed toward said surface for measuring radiation impinging thereupon from the specimen.
Claim 10
Dependent Claim
41 words
The optical instrument of claim 1 wherein said beam redirecting means includes a double-sided mirror for redirecting the reflected beam onto the specimen along the optical axis and said instrument operates to measure characteristics of the specimen through a reflective/refractive regimen.
Claim 11
Dependent Claim
43 words
The optical instrument of claim 1 wherein said beam redirecting means includes a beam splitter positioned on the optical axis to direct said beam toward the specimen along said optical axis and said instrument measures characteristics of a specimen through an interferometric regimen.
Claim 12
Dependent Claim
17 words
The optical instrument of claim 9 including means therein for sensing self-displacement with respect to the specimen.
Claim 13
Dependent Claim
14 words
The optical instrument of claim 1 wherein said beam redirecting means comprises a waveguide.
Claim 14
Dependent Claim
14 words
The optical instrument of claim 12 wherein said waveguide comprises a fiber optic bundle.
Claim 15
Dependent Claim
67 words
The optical instrument of claim 1 having beam reflecting means that directs the beams projected onto said surface and reflected from said surface to be reflected so as to intersect each other at the specimen and by decreasing the common volume of the beams engaged in said intersection maximizing the optical power contained within such volume to thereby improve the accuracy of measurements made by said instrument.
Claim 16
Dependent Claim
62 words
The optical instrument of claim 1 wherein said source of light for providing a beam of light intersecting the specimen at an oblique angle comprises a source of light positioned to one side of the optical axis of the instrument and a back-to-back apertured photosensor means is positioned between the light source and the specimen for measuring a characteristic of the specimen.
Claim 17
Dependent Claim
69 words
The optical instrument of claim 1 wherein said source of light for providing a beam of light intersecting the specimen at an oblique angle comprises a source of light positioned to one side of the optical axis of the instrument and a waveguide means is provided in the instrument for redirecting the beam reflected from the specimen to travel along the optical axis of the instrument toward the specimen.
Claim 18
Dependent Claim
109 words
The optical instrument of claim 1 wherein said source of light for providing a beam of light intersecting the specimen at an oblique angle comprises a source of light positioned to one side of the optical axis, wherein a second source of illumination is provided for illuminating the specimen and reflective means is provided on the optical axis of the instrument for directing light from the second source of illumination onto the specimen along the optical axis thereof, said light sources being operable independently of one another to make possible the separate measurement of beams reflected from normal and oblique illumination to thereby enhance the accuracy of the instrument.
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| 3.5 Years (Year 4) | 1995-04-07 | 1995-10-07 | 1996-04-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-04-07 | 1999-10-07 | 2000-04-07 | $3760.00 | Window Closed / Lapsed |
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